GB735378A - Heat treatment of ring-shaped articles - Google Patents

Abstract

735,378. Heat treating. MORRIS MOTORS, Ltd. April 30, 1954 [Feb. 21, 1953], No. 4906/53. Class 72. [Also in Group XI] Ring-shaped articles, e.g. engine starter rings, are heat treated by two heating devices of the same power which are initially juxtaposed and then moved in opposite directions at a uniform speed along a circular path concentric with the work, each device being trailed by a quenchant jet until they meet again, whereupon they are put out of action and simultaneously an auxiliary quench is automatically applied to the last heated zone of the work. Highfrequency heating apparatus is preferably used (see Group XI) and comprises loop inductors 18A, 19A fed from, and supported by, rotary transformer secondaries 3, 3A surrounding a fixed common primary 1, 1A. The inductors. are initially juxtaposed in overlapping relationship and quenchant jets 28, 29, Fig. 2, travel with them. The work 30 is supported on a flange 31 of a cover 32, and each inductor travels through a little less than 180 degrees in a horizontal plane. A switch 34 is actuated by an arm 35 to cut off the supplies to the motor, which drives the inductors through gears 10, 12, 16, 17, and to the inductors when the travel is completed, and simultaneously an auxiliary quench 36 is operated to cool the last heated zone of the work. Alternatively a pair of flames of equal intensities may be used.